    :req-un [::transformation.trim-doublespace/args
             ::transformation.engine.s/onError
             ::transformation.engine.s/op]
-   :opt-un [::transformation.engine.s/namespace
-            ::transformation.engine.s/namespace]))
+   :opt-un [::transformation.engine.s/namespace]))
 
 (create-ns  'akvo.lumen.specs.dataset-version.transformation)
 (alias 'db.dsv.transformation 'akvo.lumen.specs.dataset-version.transformation)

            ::transformation.engine.s/op]
   :opt-un [::transformation.engine.s/created
            ::transformation.engine.s/namespace]))



(create-ns  'akvo.lumen.specs.transformation.change-datatype)
(alias 'transformation.change-datatype 'akvo.lumen.specs.transformation.change-datatype)

  (s/keys :req-un [::db.dsv.column.s/columnName]))


(defmethod op-spec "core/delete-column"  [_]
  (s/keys
   :req-un [::transformation.delete-column/args
